Yes, absolutely. Most of my glazes flow enough that I don't really need to worry, but the speckled glazes I've been working with recently are noticeably thicker at the rim because they don't move much at all. It still probably only amounts to less than a millimetre but would be worth bearing in mind at least.
I thought I was safe from Maths going down the pottery route!!! I have zero ability with numbers, zilch, nada. My brain spits digits back out, decimals, division, all the evil math thingies 😔 Beautiful pot though, love its shape
I feel the same as you, my husband teaches high school math....lol. I bet you will understand this because I needed him to and he explained it to me an my level, probably grade 5 hahahha. If you want the opening to be 5 cms that is 50 mm. If the shrinkage rate is 12% here is the math. 100%-12%=88% so you want to divide your desired number by .88. So 50mm divided by .88=56mm. Hope that helps. So you throw the opening at 56mm.
My manufacturer gives me two ciphers: contraction at dryness 6,8%, contraction when bisqued -0,4%. I don't quite understand it... Why minus??? And... shall I add these two ciphers?
Thank you !!!!
THANK YOU SOOOOOO MUCH FIR THIS!!!
Really helpful thank you 👍🏻
Lovely pot with this tight fit!! Thank you for explaining the calculating :-) Would you also consider the thickness of some glazes when you throw?
Yes, absolutely. Most of my glazes flow enough that I don't really need to worry, but the speckled glazes I've been working with recently are noticeably thicker at the rim because they don't move much at all. It still probably only amounts to less than a millimetre but would be worth bearing in mind at least.
I thought I was safe from Maths going down the pottery route!!! I have zero ability with numbers, zilch, nada. My brain spits digits back out, decimals, division, all the evil math thingies 😔 Beautiful pot though, love its shape
Haha, I'm sure you're far more capable then you think!
I feel the same as you, my husband teaches high school math....lol. I bet you will understand this because I needed him to and he explained it to me an my level, probably grade 5 hahahha. If you want the opening to be 5 cms that is 50 mm. If the shrinkage rate is 12% here is the math. 100%-12%=88% so you want to divide your desired number by .88. So 50mm divided by .88=56mm. Hope that helps. So you throw the opening at 56mm.
Hope this isn’t a silly question, but is this for both height and width?
Yes, the clay shrinks uniformly in all directions, so it'll be the same proportion smaller in height, width, and depth.
Content on FIRE! BLESSINGS, -Kate
My manufacturer gives me two ciphers: contraction at dryness 6,8%, contraction when bisqued -0,4%. I don't quite understand it... Why minus??? And... shall I add these two ciphers?